This document discusses sexual reproduction in animals. It explains that sexual reproduction involves the union of male and female gametes, sperm and egg, which have half the number of chromosomes. It describes the process of gametogenesis where sperm and eggs are produced in the testes and ovaries. Fertilization is when a sperm unites with an egg to form a zygote with a full chromosome number. Fertilization can be internal, where fertilization occurs inside the female's body, or external, where fertilization occurs outside the female's body after egg laying. After fertilization, the zygote develops into an embryo either inside or outside the female's body.

1. Activity 1: Match It UP

2. SEXUAL REPRODUCTION

3. Sexual Reproduction
is when two organisms reproduce
using their gametes the sperm and
egg cell both have a haploid number
of chromosomes.

4. Sexual Reproduction in animals
-should have Male and Female
-involves sex organs (Gonads) to produce
gametes
Ovaries-Ova or eggs (Haploid)
Testes-Sperm (Haploid

5. How are gametes made?
- Gametes are made through the
process Gametogenesis.
Oogenesis- process for producing
egg cell.
Spermatogenesis-process for
producing sperm cell.

6. Spermatogenesis & Oogenesis

8. Hermaphrodites
Ovaries and testes in same animal
In slow or sessile organisms (worm ,hydra
snail)
Self fertilization rare.

9. Fertilization-the union of egg cell and
sperm cell.
How does fertilization happen?
Sperm swim to egg
Sperm releases enzymes to make hole in egg
Sperm injects nucleus into egg
Fertilization membrane form around egg
No future fertilization
Joining of sperm nucleus and egg nucleus
Form diploid zygote

10. Types of Fertilization
1. Internal Fertilization
-The egg is fertilized by sperm
inside the female’s body.
-Ex. Mammals, reptiles, insects, spiders

11. 2. External Fertilization
The egg is fertilized by sperm outside the
female’s body.
The female lays the eggs and then the male
fertilizes them.
Ex. Fish and some amphibians

12. What happens after fertilization?
-The zygote develop.
Could developed inside the female’s body or develop outside.
1. Oviparous animals- animals that lay their eggs, with little or no
other embryonic development within the parent.
Ex. Chicken, birds, lizards, crocodiles
2. Viviparous animals – animals that bring forth live young that have
developed inside the body of the parent.
Ex. Human, monkeys, dogs, cats, dolphins
Embryology=Study of embryo development